Repulsion vane instrument



May 9, 1939.

D. A. YOUNG ET AL REPULSION VANE INSTRUMENT Original Filed April 16,1936 WITNESSES: M /M INVENTORS. Doug/ass A. Young and AF/Y/Qv L.flernarde BY l f ATT EY Patented May 9, 1939 om-reo- TATES 2,157,941PATENT oFFicE REPULsI'oN VANE INSTRUMENT 'i iougl ass A. Young, Eastorange, and fieiiryi.

house Electric & Manuf cturing company, st- Pitt'sbui'gh, Pa., acorporation of Pennsylvania Application April s, 1935,- SeriakNo. 74,714

, Renewed November 1, 193-8 8 Claims.

The present invention relates to electrical meastiring instruments,- andmore particularly to an improved means for adjusting and calibratingindicating'i-nstruments of the so-called repulsion van-e type;

I-n instruments of this type, a pivoted vane and a stationary vane areusually mounted in parallel relation within a solenoid which is to beenergized in accordance with the quantity to be measured. The magneticfield of the solenoid acts the two vanes to cause a repulsion of thepivoted vane, with respect to the stationary vane. Tkiepivoted vane isnormally biased toward the stationary vane and controls anindicatingpointer cooperating with a scale to indicate the magnitrade. or theenergization of the solenoid.

In calibrating instruments of this character, considerable diificultyhas been experienced in obtaining an adjustment which is s-ufiicientlylarge and at the same time; not so large that scale distortionwiiiresuit; that is; to be able to properly calibrate the instrument butat the same time; to have a standard printed scale for aili'icistrimhents of thesame ran e;

1 1i the prior art,- it has been necessary to either alter resistance orthe solenoid winding or,

in: some cases, to movetne winding axially of the vanes to obtain thedesireddeflection of the pivoted vane for a given energi'zatiori of thewinding;

It is afiobject dithe present invention to avoid the difliculty andexpense inherent in pridr art eXpledi-ents for calibrating an instrumentof the repulsmg vane type, and at the same time to obtain a range ofcalibration which is larger than that heretofore obtained; Withoutdistorting the instrument scale to an appreciable extent.

Other objects ofthe' invention will be apparent from the followingdescription'and accompanying drawing, wherein: Figure I is a View inperspective, with parts broken away, e'i-iibodying the presentinvention; @Figi; 2= is a view in section, with parts broken away; orthe calibrating" device" constituting the invention; Y Pig.- 3 1's aview in end elevation of aportion of the 's'trn'etiife shown 2-; and

' a view iris'ection o'rithe line I V IV of Referring more specificallyto the drawing, the movement or the indicating instrument embodymg theiIW-fitihcomprises a coil-or winding 2 to be energized from the circuitto be measured.

iWithin the solenoid 2 is disposed a body 4 of insulating materialhaving an enlarged flange 6 overlying one end of the solenoid 2' andprovided with a chamber 8.

Within tnechamber 8. is disposed a shaft l pivotfillyfiioiifited at. oneend thereof in a bearing l2 secured to the rear wall of the chamber andpivotally supported at the opposite end in a bracket t4 secured: to theflange 6. A vane t6 oi? magnetic material: is secured to the shaft alongone of its edges any suitable manner for rotationwith the shaft l8 andthe free end of the shaftearries an indicating pointer i8 forcooperation with a scale in a usual manner; The pointer is biased to azero position by a spiral spring l9.

The chamber 8 is so shaped that the free edge of the vane i6 isrelatively close; to the chamber wall so that an air damping effect isobtained, when the front of the chamber is closed by asuitable plate,not shown, disposed in the recess 20.

The stationary vane comprises arod 2 2 of magnetic material disposedparallel to the shaft W in an elongated recess in the wall of thechamber 8'. In instruments of this class in the prior art, the rod- 22was rigidly secured in its: desired pos'itiom According to the p'reseritinvention,- however, the rod 22 is secured at one end: thereof toa hub24 having areduced portion 26 extending through the rear wall ofthexehamber 8.

Referring to'Figss 2 and 45, it will be noted that the rod 22 is mountedecc'entricalsiy with respect to the hub 26, which is" an importantfeature of the invention. Although the hub 24 and the means of securingit to the rod 22 may be of any desired construction, it has been foundadvam tageous to make the hub Z i of extruded: material,- such asaluminum or an alloy thereof. The ma terial extruded to substantiaiiythe shape shown in Fig.4, extruded piece may then be turned dOWH lid"the Size Of pditifi 25; a I

groove 28* out therein, and a slot provided the free end so tofaeiiitaterotation' of the hub, rod- 22. is their stance into theiongitudinar notch the hub 24 to be reiiiovabl y retained in thatposition; 7

Referring: to Figs; 2 and 3, the hub 24! is re-- silientiy retained inany position to whichi-t may be rotated by a:- spring member 32 secured:at one end to the rear face'of thebody t-biy means" or a screw 34; andthe free" end ofrthe spring 32 is slottedto' embrace the reduced portion28 on the hub 14, as indicated; practice; it has been foundthafi'the's'piing 32 acting the hub 2, efiici-ently maintains the hub ina; desirm positionand at the Sansone; permits easy rotation of the hubby means-oi asniall screwdriver engaging the screw head 30.

In calibrating an instrument of the construe tion above described, thewindingor solenoid 2 is energized" at a prdetenn-ined value of currentor voltage, and ordinarily, calibration with be required to bring: thepointer? l 8-into registration with the. proper scale division. This isaccomf plished in the present invention by merely ro tating the hub 24which swings the bar or vane nu bx is, an instrument properly calibratedto a point of half its scale length may show an improper calibration atgreater or smaller energization of the winding 2, necessitating,ordinarily, a difierent scale for different instruments. In the priorart, this distortion was such that a calibration of plus or minus 2% wasall that could be obtained Without using a different scale, and themethod of calibrating was so long andtedious as to be very expensivefrom a manufacturing pointof View. In applicants construction, it willbe noted that as the hub 24 is turned, the vane 22 has a cyclic pathbringing it closer to the shaft ill, and at the same time, varies itsposition with respect to the lateral dimension of the vane [6. Thiscompound movement, it is believed, results in applicants remarkablecalibration range and compensates for scale length distortion usuallyobtained with a calibrating range of this magnitude:

Quite obviously modifications may be made in the structure specificallyshown and described without departing from the scope of the invention asset forth in the appended claims.

We claim as our invention:

1. In an electrical instrument of the repulsionvane type including achambered member having an end wall and a winding surrounding saidmember for energization in accordance with a quantity to be measured, amoving vane in said chamber mounted for pivotal movement about one. ofits edges, a stationaryvvane comprising a rod and means for mounting itparallel to said moving vane comprising a hub having a reduced portionon one end thereof, an aperture in said end wall through which saidreduced hub portion is proportioned to extend, a resilient clip andmeans for mounting it to retain said hub in operative position .andfrictionally restrain it against rotation, and means for securing oneend of said rod to said hub eccentric to the axis of rotation of saidhub.

2. In an electrical indicating instrument including a housing having anend wall, a movable vane of magnetically conducting material and means.for mounting it in said housing for pivotal movement on an axis atright angles to said wall, a stationary rod of magnetically conductingmaterial for disposition parallel to the axis of pivotal movement ofsaid vane to repelthe latter when the Vane and rod are subjected to amagnetic field, means for adjustably supporting said rod in suchposition comprising a substantially; cylindrical member having a reducedportion extending from one end thereof for extension through said'endwall from within said housing, a circumferential groove in said reducedportion beyond said wall, a spring clip secured at one end to theoutside of said wall and having its other end disposed in said groove,said clip being proportioned and formed to frictionally restrain saidcylindrical member against rotation, and means for securing one end ofsaid rod to said member withinsaid housing with the longitudinal axisof, the rod parallel to the axis of rotation of the member.

3..In an electrical instrument of the repulsion vane type including achamber in which a pivotedvane is mounted, a stationary vane and meansfor adjustably mounting it to repel said pivoted vane when the chamberis disposed in a magnetic field, comprising a supporting member securedto one end of said stationary vane and having a portion extendingthrough an end wall of said chamber for rotatably mounting said memberfor rotation about an axis eccentric with respect to said stationaryvane, and a resilient member secured to said end wall and engaging saidmeans to retain it in operative position and frictionally restrain therotation of the supporting member.

4. In an electrical instrument of the repulsion vane type, meansdefining an elongated chamber having an end wall, a strip of magneticmaterial and means for pivotally mounting it for rotation about alongitudinal edge thereof parallel to the longitudinal dimension of saidchamber, said chamber being arcuate in cross-section with a radiusslightly larger than the width of said strip, and having fiat walls atthe limits of pivotal movement of the vane, a recess in one of said flatwalls extending longitudinally of the chamber, a rod of magneticmaterial in said recess, and means for laterally adjusting the :rod insaid recess with respect to the axis of rotation of said strip.

5. In an electrical instrument of the repulsion vane type, meansdefining an elongated chamber having an end wall, a strip of magneticmaterial and means for pivotally mounting it for rotation about alongitudinal'edge thereof parallel to the longitudinal dimension of saidchamber, said chamber being arcuate in cross-section with a radiusslightly larger than the width of said strip, and having fiat walls atthe limits of pivotal movement of the vane, a recess in one of said fiatwalls extending longitudinally of the chamber, a rod of magneticmaterial in said recess, and means for laterally adjusting the rod insaid recess with respect to the axis of rotation of said strip,including means constituting an en--v largement on one end of said rodand having an eccentric portion extending through said end wall forrotation with respect thereto, the axis ofsaid extending portion beingparallel to the axis of said rod.

6. In an electrical instrument of the moving iron type, a magnetic vanerotatable about an axis, and a magnetic member having a dimension radialfrom said axis which is substantially smaller than the dimension of saidvane radialfrom said axis, said magnetic member being adjustable forvaryingits distance from said axis.

7. In an electrical instrument of the moving iron type, a magnetic vanerotatable about an axis, and a magnetic member having a dimension radialfrom said axis which is substantially smaller than the dimension of saidvane radial from said axis, said magnetic member beingrotatable foradjustment eccentrically about asecnd axis spaced from said first-namedaxis.

8. Inan electrical instrument of the moving iron type, a magnetic vanemounted for rotation about a first axis, and a magnetic member providedwith a cylindrical surface'having an axis substantially parallel to saidfirst axis, the diameter of said cylindrical surface being substantiallysmaller than the dimension of said vane radial from said first axis,said magnetic memberbeing adjustable for varying its distance from saidfirst axis. T t DOUGLASS A. YOUNG.

HENRY L. BERNARDE.

